High performance abrasive particles for use in finishing and polishing include grit particles and composite particles. Grit particles are solid grains, while composite particles are formed from an aggregate of small primary grit particles bound together within a nanoparticle binder.
Conventionally, when grit particles are used to finish or polish a surface to a desired smoothness, the polishing process occurs in several polishing steps using abrasive grains of varying grit size. Each successive polishing step involves the use of grit particles of decreased size. The surface is first polished with a relatively coarse abrasive material and then polished again with a somewhat finer grit abrasive material. This process may be repeated several times, which each successive re-polishing being carried out with a progressively finer grit abrasive until the surface is polished to the desired degree of smoothness.
It has been found that use of composite particles offer the efficiency of achieving comparable surface smoothness in fewer steps, or in even only a single polishing step. It is believed that the primary particles, the nanoparticle binder, and the aggregate as a whole each achieve the steps of polishing necessary to obtain the final desired surface smoothness. Composite particles are therefore favored in applications requiring fast ultra-fine polishing.
Nevertheless, a need exists for an abrasive article and a method of polishing that achieves improved surface smoothness and longer product life.